1. Field of the Invention
The present invention relates to solar modules for generating electrical energy, and more particularly to photovoltaic modules integrated into a laminated, weather resistant sandwiched module for installation on roofs, and more particularly to apparatus and method for edge seals for such photovoltaic modules.
2. Description of the Related Art
Conventional photovoltaic modules for generating electrical power for residences and businesses are often flat and are placed on a portion of a roof that is exposed to the sun. Historically, such modules were placed on structures erected on the roof to support and protect the modules. More recently, photovoltaic modules have become available that can be mounted directly on a flat or tilted roof. See, for example, US Patent Application Publication No. 2005/0178248 A1 to Laaly et al., (the entire contents of which are incorporated herein by reference), which discloses a module that incorporates a roofing membrane into the module structure. The module is intended to be installed on a new roof or replacement roof with the membrane providing moisture protection for the underlying structure as well as providing electrical power.
See also U.S. Pat. Nos. 7,531,740 and 7,557,291 both to Flaherty, et al., the entire contents of both of which are incorporated herein by reference. These patents disclose such photovoltaic modules for roof-top installation.
A problem with above mentioned direct roof top attached crystalline silicon photovoltaic cell based solar modules is their tendency to retain water or other deleterious solids and/or liquids around the edge seals. See, for example, FIG. 2 of U.S. Pat. No. 7,531,740. After a rain, or after a cleaning with water and chemicals, such liquids and/or solids are often retained in the area adjacent the upper protective layer 110 and the frame half 180. After some time, these liquids can deteriorate the upper protective layer and/or the half frame, and leak into the module itself, shorting-out one or more of the solar cells. Another known problem with prior designs is that often the bottom frame half 180 is thicker than pressure sensitive adhesive (PSA) tape layer 160, thus reducing the ability of the module 100 to stick securely to the roof around the frame of the module. Thus, what is needed is a photovoltaic module with improved edge seal design to prevent such liquid damage and to enhance the ability of the module to stick to the roof.